nx 10 flash

hi everybody!
I know about the others samsung flash, but they are very very expensive.

So if using other flash as for example "nikon" one, I will not have the light exposure meter (as camera do with all external flash), and in addition I will see the AMOLED screen dark , like flash option is not switched-on, right?
this is not a great problem for me...
I would like a Metz or other brands external flash...mmmmmmmmmmmm
thank u to all
sorry for my bad english!